What are your thoughts on using wild plants gathered from local streams or ponds for use in a tank? Just curious, kinda seems wasteful to me to drive by lots of local plants to go buy something from a store. I know there's a concern about pesticides and chemicals, is there something I can do to mitigate this issue? perhaps giving the plants a long soak time (2 weeks or more) with maybe daily 50% changes before introducing fish?

You will also want to be very careful in which type of plants you use. Remember that a fish tank is a contained environment. Do research on the plants you are considering for the tank to make sure they do not release any unwanted levels of ammonia, etc.

Personally, I really wouldn't. There are just too many variables to control and I have had problems even with driftwood that I have gathered despite my diligent scrubbing and boiling for hours. A fishtank is a closed environment so even something that looks fine can have terrible effects on aquarium fish (such as tozxins or parasites)......I just wouldn't chance it.